Cam-operated electric timing mechanism with improved adjustable pin coding and retaining structure

ABSTRACT

A mechanical memory of the code pin switch activating type employs a plurality of compression loaded code pin members arranged in a containing means which permits lateral translation of each of the pins in a row orientation while constraining the pins from translation transverse the pin row. The pins are substantially square headed and are formed with a head slot which may be selectively oriented so as to be coextensive with or transverse of the pin row axis. Cooperating switch activating members are loaded against the pinheads such that selected pin slot orientations define respective first and second positions of the actuator member.

[451 Jan. 25, 1972 Laschenski...................,200/38 CA XGrundfest........... ....200/8 R X Fredell..........,..................200/38 CA ABSTRACT pin switch activating type aded code pinmembers ch permits lateral translantation while constraining the pinrow. The pins are e formed witha head slot so as to be coextensive withspective first and l 1 Claims, 7 Drawing Figures 3,194,086 7/19653,330,917 7/1967 3,538,284 11/1970 Alexander et a1.. 3,588,396 6/1971Primary Examiner-.1. R. Scott Attorney-Richard W. Anderson and Robert J.Crawford A mechanical memory of'the code employs a plurality ofcompression 10 arranged in a containing means whi tion of each of thepins in a row orie the pins from translation transverse substantiallysquare headed and ar which may be selectively oriented or transverse ofthe pin row axis. Cooperating switch activating members are loadedagainst the pinheads such that selected pin slot orientations define resecond positions of the actuator member.

pids,

MECHANISM WITH IMPROVED ADJUSTABLE PIN CODING AND RETAINING STRUCTURE[72] lnventors: Lester W. Haerther; Joseph J. Earley,

both of Cedar Rapids, Iowa Collins Radio Company, Cedar Ra Iowa Mar. 1,1971 119,723

. ...........200/38 CA, 200/18, 200/153 L,

.....I-l0lh 7/08, H01h 43/10 .200/8 R, 33 B, 37 A, 38 B, 200/38 BA, 38C, 38 CA, 153 L; 74/567,568 T References Cited UNITED STATES PATENTS12/1964 Kuhl et al. .............200/38 CA X United States PatentHaerther et a1.

[54] CAM-OPERATED ELECTRIC TIMING [73] Assignee:

[22] Filed:

[21] Appl. No.:

[52] U.S.Cl........ I

[51] Int.

[58] Field of PATENTEU M25 1972 FIG. 3

FlG.2'

FIG.4

FIG. 7

INVENTORS LESTER W. HAERTHER JOSEPH J. EARLEY AGENT CAM-OPERATEDELECTRIC TIMING MECHANISM WITH IMPROVED ADJUSTABLE PIN CODING ANDRETAINING STRUCTURE This invention relates generally to mechanicalmemory systems and more particularly to an electromechanical arrangernent positioning a plurality of switches in one or the other of twopositions so as to effect a preselected permutation of relative switchpositions.

The invention is generally embodied in the provision of a plurality ofadjustable mechanical devices (herein referenced to as code pins)arranged to coact with a plurality of switch actuating members toposition a switch associated with each actuator to one of twopredetermined positions, and by means of which mechanical adjustment toeffect preselected switch position permutations of a bank of switchesmay be readily effected.

Mechanical memory systems of a type employing rows of pin memberscarried on a drum are known in the art wherein the relative positions ofthe pin members defining a given row of pins effects predeterminedposition permutations of actuating members actuated from a first to asecond position upon mechanical engagement with a pin member. Devices ofthis general type inherently define a storage problem as concerns thepin members in a bank. For example, a bank of pin members in certainsystems are positioned to one of two lateral positions along a pin rowso as to selectively engage or not engage a cooperating switchactivating arm. Obviously in such systems a lateral dimension, that is,the length required for a given row of pins, is at least double thelateral dimension defined by the pin members per se, since each pin mustbe positionable to two discrete lateral positions.

Other mechanical. memory systems employing selectively positioned pinmembers for cooperative engagement with associated switching devices maysolve the lateral storage space requirement by means which cause the pinto either project from the surfaceof a drum member carrying the pin rowor, by a radial inward positioning means, be recessed so as to notengage the cooperating one of a bank of switch-actuating members.

The present invention has as a primary object thereof the provision of amechanical memory system wherein lateral storage requirements areessentially obviated as well as radial storage requirements, by anassembly providing decided advantages of low cost and reliability due tothe simplicity of the arrangement and the minimal number of partsrequired for implementation.

A further object of the invention is the provision of a switchpositioning code pin assembly with positive detenting for both binarypositions of the individual pins.

The present invention is featured in the provision of a code pin oractuating pin assembly comprised of a plurality of compression-loadedcode pin members arranged in containing means permitting lateraltranslation of each of the code pins in a pin row and permittingrotation of each of the pin members while constraining the pin membersfrom translation transverse to the axis of the pin row. Each of the pinmembers carries a transverse slot on the face thereof which maybeselectively oriented so as to be coextensive with or transverse of thepin row axis. A plurality of cooperating switches are each provided witha switch actuating member spring loaded into a camlike relationship withthe associated one of the pin members whereby the pin slot orientationdefines respective first and second positions of the actuating memberaddressing each code pinface.

These and other features and objects of the present invention willbecome apparent upon reading the following description with reference tothe accompanying drawings in which:

FIGS. 1, 2, and 3 are respective top, side, and the bottom views of acode pin member utilized in the present invention.

FIG. 4 illustrates a plurality of code pin members arranged in aconfined and spring-loaded code pin row assembly in accordance with thepresent invention;

FIG. 5 illustrates a cooperating switch-actuating member in engagementwith a codepin; and

III

FIGS. 6 and 7 illustrate an embodiment of a plurality of rows of codepin assemblies arranged in a drumlike configuration rotation of whicheffects a preselected position permutation of a plurality of switches asdefined by the pin face slot orientation in a selected code pin rIow.

As above described, the present invention provides for a bank or row ofcode pin members, the mechanical positioning permutations of whicheffect predetermined electrical switch connections of an associated bankof switch members. Each switch member includes an actuating or contactarm in spring loaded mechanical engagement with an individual one of thepins in the row. As will be described, a preselected permutation of codepin orientations in a row effects a relative position permutation of anassociated bank of switches. By embodying a plurality of rows of pinmembers each adjusted to one of two position orientations, an associatedbank of switches may be selectively actuated to define a predeterminedpermutation of switch positions in accordance with the, mechanicalmemory" set in a selected pin row which is caused to engage theplurality of switches.

The basic code pin member of the present invention is illustrated inFIGS. 1, 2, and 3. The code pin 10 is formed with a substantially squareface member .11 the corners 13 of which may be formed with apredetermined radius. As illustrated in FIG. 1, the face 11 has formedtherein a transverse slot 12. The portion of the pin opposite the facemember 11, as best shown in FIGS. 2 and 3, is formed with a radialgroove 8 such that the pin member is terminated. in an annular ringportion 14.

A basic pin row assembly in accordance with the present invention isillustrated in FIG. 4. Fourpin members l0a-l0d are shown in stackedposition and retained by means of guide rail members 15 and 16 which arearranged in parallel-spaced relationship between fixed mounting members18 aid. The radial groove 8 formed in eachof the pin members l0a-10dcaptivates the pin members within the guide rail asembly but permitsrotation of each of the pin members l0a-I0d within the plane of theguide rails. The length of the guide rails l5 and 16 is in excess ofthat defined by the lateral dimensions of the faces 13 of each of thepin members, and a spring loading means comprising a loading member 9and compression spring 17 urges the pin members 10a-l0d intospring-loaded juxtaposed relationship.

Loading member 9, unlike the pin members I0a-l0d, is formed with opposedslots into which guide rails 16 and 17 are received, and thus member 9may'translate along the pin row axis but is constrained from rotation.The spring loading means establishes a relative position detent asconcerns the squareheaded pin members l0a-l0d. When any one of the pinmembers l0a-l0d is rotated in detented steps, the detent action isaccomplished as the longitudinal dimension of the pin being rotatedchanges through the rotation action causing the spring 17 to first befurther compressed and then released to realign the square pin heads tothe stacked position illustrated in FIG. 4. The comers of each of theheads of the pin members l0al0d may be formed with a slight radius andthe pins themselves comprised of an insulating molding material ofdesired lubricity to permit rotation of any one of the pin members tochange the position. permutation of the pin row without transmittingrotation to other pins in the row.

FIG. 5 illustrates the manner in which the relative orientation of theface slot in any one pin member 10 in the assembly of FIG. 4 effectsbinary positioning of a cooperating switch means. Pin member is depictedin the cross section view of FIG. 5 with its face slot 12 aligned invertical position. A cooperating switch contact arm 20, which may beconstructed of a resilient material, is illustrated in spring-loadedrecessed position within the slot 12 so as to establish an electricalconnection between switch contacts 26 and 21. With the code pin 10coriented 90 to the illustrated position, it is seen that the face slot12 would be transverse the longitudinal axis of the contact arm member20 (rather than coextensive therewith) so as to urge the contact arm20into the dotted configuration position 20' and complete connectionbetween contact 26 and contact 22. It is to be understood that'theparticular contact arm 20 of FIG. 5 might be constructed of a resilientconduc- "t ive member anchored in a base or mounting means 25 at one end24 thereof and might be formed with a suitable projection 23 for desiredcooperative engagement with the pin slot 12 to effect the connectionsbetween contact 26 and one or the other of switch contacts 21 and 22.

Although not particularly illustrated in FIG. 5, it is to be un derstoodthat a plurality of contact arms 20 associated with a bank of switchesmight be employed with each arm being positioned in accordance with theslot orientation on the head of an engaging one of the code pin members1011-1011. The switch position of each of a plurality of switchesaddressing the code pin stack of FIG. 4 is thus seen to be determined bythe head slot orientation in the associated one of the code Pll'lS.

The basic pin row assembly of FIG. 4 may be repeatedly embodied todefine paralleled rows of pins as defined by a circu lar patternillustrated in FIGS. 6 and 7. By configuring the guide rail members andcode pin rows in a circular pattern as depicted in FIG. 6 a basic presetmemory drum is defined. FIG. 6 depicts three adjacent rows of pinmembers 28, 29, and 30 positioned about the periphery of a drum member27, it being realized that the entire surface of the drum may beconfigured with code pin rows. Rotation of the drum 27 about its axis 31by means of a mechanical link 32 with a channel select knob 33,positions selected ones of the plurality of code pin rows intocooperative relationship with a plurality of switch contact arms 20. Atypical configuration used for UHF radio control units might contain 15code pins in each row and a total of stacks or rows carried about theperiphery of the drum 27 to permit a channel preset capability. Theparticular permutation of slot orientation of the code pins in each roweffects a predetermined permutation of the associated switches in thebank, and selected permutations may be utilized to establish tuningcodes for 20 preset channels.

it is to be realized that, although the depicted embodiment illustratesconductive switch contact arm members being positioned in accordancewith the relative orientation of the code pin slots, the switch armspositions might control the actuation of an associated microswitch.Further, one of the pair of switch contacts 21 and 22 illustrated asbeing associated with each of the contact arms might be embodied in orconnected to a single grounding bus bar by means of which predeterminedones of the contact arms 20 may selectively effect a grounding of switchterminal 26 depending upon the orientation of the cooperating code pinhead. In general it is seen that the particular orientation of the codepin face slots defines one of two possible electrical switchingfunctions associatedwith that particular pin and numerous electricalcontrol systems might be embodied with the contact arm or switchposition to effect a particular preselected control.

The basic configuration of the present invention is seen to provide ameans of selectively actuating a plurality of switches by code pinactivating means which requires minimal storage capacity. The storage"need only comprise a lateral or longitudinal space as concerns the pinrow to permit the slight translation necessitated by the diagonaldimension of the pin head as the pin is rotated from one detentedposition to another and to facilitate the compression spring loadingmeans for the pin row.

Obviously other forms or shapes of material could be used to adapt tothe basic memory drum application of the present invention. For example,other retaining means for the code pin assembly might be employed topermit the necessary pin rotation and translation of pins along the axisof the pin row to permit pin face orientation changes while constrainingthe pins from motion transverse that of the row axis.

The pin assembly of the present invention is seen to possess uniqueproperties of small size with minimal storage space requirements toeffect the pin function, extremely low cost, positive displacementcontrol of the cooperating switch contacts, positive detenting for bothbinary positions, captive pin design, and ease of resetting the codepins when required.

Although the present invention has been described with respect to aparticular embodiment thereof, it is not to be so limited as changesmight be made therein which fall within the scope of the invention asdefined in the appended claims.

We claim:

l. A mechanical memory system for effecting a predetermined permutationof switch positions of a plurality of switching means comprising, aplurality of code pin members; each pin member having a substantiallysquare face member, a slot formed in said face member and extendingtransversely between parallel sides thereof; means for containing saidplurality of pin members in a row with coplanar face members, saidcontaining means permitting rotation of each of said pin face memberswithin the plane defined by said pin face members, said containing meanspermitting translation of said pin members along the axis defined bysaid row of pins, spring loading means cooperating with at least one ofthe pins in said row and urging said plurality of pins into acompression loaded parallel-sided orientation; said plurality ofswitching means arranged in a row with each of said switching meansincluding an actuating arm member in spring loaded relationship with theface member of an associated one of said plurality of pin members, eachof said actuating arm members being urged into a first position when acooperating one of said pin member slots is coextensive with the axis ofsaid switch actuating arm and being urged into a second position when acooperating one of said pin member slots is transverse the cooperatingactuating arm axis, and means responsive to said first and second switchactuating arm positions to effect respective predetermined first andsecond electrical interconnections.

2. A mechanical memory system as defined in claim 1 wherein said pin rowcontaining means comprises first and second fixed mounting surfacesbetween which said pin row is confined, said mounting surfaces beingspace separated by a predetermined distance in excess of the pin rowlength, said spring loading means comprising a compression spring membercarried with the confines of said pin row and acting along the pin rowaxis to urge said plurality of pin members into said spring-loadedparallel-sided orientation.

3. A mechanical memory system as defined in claim 1 wherein said pin rowcontaining means comprises a pair of parallel spaced guide rail membersfixed between first and second mounting plate members, each of said pinmembers having formed therein a radial groove the diameter of whichsubstantially equals the distance by which said guide rail members areseparated, said rail members being received into said pin member radialgrooves, whereby said pin members are constrained from translationtransverse that of said guide rail axes with limited translationpermissible along the pin row axis parallel to that of said guide railmembers and with each of said pin members being rotatable within theplane defined by said pin face members.

4. A mechanical memory system as defined in claim 3 wherein each of saidsquare pin member faces is formed with rounded comers of predeterminedradius, said pin members being constructed of a lubricous materialpermitting a selected one of said plurality of pin members to be rotatedand effect translation of adjacent ones of said pin members withouteffecting rotation thereof.

5. A mechanical memory system comprising a plurality of 7 code pinmembers arranged in a row, each said code pin member being formed with asubstantially square face, means for containing said pin members in saidrow to permit rotation of each pin member within the plane defined bysaid pin member faces and to permit translation of said pin membersalong the axis of said pin row while constraining said pin members fromtranslation transverse that of said pin row axis, spring loading meanscooperating with at least one of the pin members in said row and urgingsaid plurality of pin members into a compression loaded parallel-sidedorientation, each of said pin member faces having a transverse slotextending between parallel sides thereof; a plurality of switching meansarranged in a row, each said switching means including an actuating armmember adapted to be urged into spring-loaded engagement with the faceof an individual associated one of said pin members in said row, saidactuating arm members having at least a pin face addressing portionthereof with transverse dimension less than that of the width of saidpin face slots, whereby those of said actuating arm members addressing apin face the slot of which is coextensive with the actuating arm memberaxis are positioned to a first position and those of said actuatingmembers addressing a pin face the slot of which is transverse theactuating arm axis are positioned to a second position, and electricalcontact means associated with the actuating ann member of each of saidswitching means to effect predetermined first and second electricalconnections in response'to respective first and second'positions of theassociated actuating arm.

6. A mechanical memory system as defined in claim 5 wherein said pinmembers are fonned of an insulating material, said switching meansactuator arm members comprising a conductive material, one end of eachsaid actuating arm member comprising a first output terminal, andfurther contact means adapted to make a first predetermined electricalconnection with the other end of said actuating arm with said actuatingarm in the first position thereof, and a second predetermined electricalconnection with the other end of said actuating arm with said actuatingarm in the second position thereof.

7. A mechanical memory system as defined in claim 5 wherein each of saidsquare pin member faces is formed with rounded corners of predeterminedradius, said pin members being constructed of a lubricous materialpermitting a selected one of said plurality of pin members to be rotatedand effect translation of adjacent ones of said pin members withouteffecting rotation thereof.

8. A mechanical memory system comprising a plurality of parallel rows ofcode pin members; each of said plurality of rows of code piri memberscomprising a plurality of code pin members arranged in said row, eachsaid code pin member being formed with a substantially square face,means for containing said pin members in said row to permit rotation ofeach pin member within the plane defined by said pin member faces and topermit translation of said pin members along the axis of said pin rowwhile constraining said pin members from translation transverse that ofsaid pin row axis, spring loading means cooperating with at least oneofthe pin members in said row and urging said plurality of pin membersinto a compression loaded parallel-sided orientation, each of said pinmember faces having a transverse slot extending between parallel sidesthereof; a plurality of switching means arranged in a row parallelthatvof said rows of code pin members; each said switching meansincluding an actuating arm member adapted to be urged into spring loadedengagement with the face of an individual associated one of said pins ina selected one of said rows of code pin members, said actuating armmember having a transverse pin addressing dimension less than that ofthe width of said pin face slotswhereby those of said actuating armmembers addressing a pin face the slot of which is coextensive with theactuating arm member axis are positioned to a first position and thoseof said actuating arm members ad-v dressing a pin face the slot of whichis transverse the actuating arm axis are positioned to a secondposition, electrical contact means associated with the actuating armmembers of each of said switching means to effect predetermined firstand second electrical connections in response to respective first andsecond positions of the associated one of said actuating arm members,and means for selectively positioning a selected one of said rows ofcode pin members into cooperative engagement with said plurality ofswitching means.

9. A mechanical memory system as defined in claim 8 wherein the pinmember containing means for each of said rows of pin members comprises apair of parallel-spaced guide rail members fixed between first andsecond mounting plate members, each of the pin members in a row of saidpin members having formed therein a radial groove the diameter of whichsubstantially e uals the space separationpf said guide rail member pair,sai rail mem rs being received into said pin member radial grooves,whereby said pin members are constrained from translation transversethat of the axes of said a guide rail members with limited translationpermissible along the pin row axis parallel to that of said guide railmembers and with each of said pins in said row being rotatable withinthe plane defined by said pin face members in said pin row.

10. A mechanical memory system as defined in claim 9 wherein said pairsof parallel-spaced guide rail members comprise adjacent ones of aplurality of guide rail members arranged about the periphery of a drum,and said means for selectively efi'ecting cooperative engagement betweena selected one of said rows of pin members and said row of switchingmeans comprises means for rotating said drum to a preselected angularposition.

11. A mechanical memory system as defined in claim 8 wherein each ofsaid square pin member faces is formed with rounded comers ofpredetermined radius, said pin members being constructed of a lubricousmaterial permitting a selected one of said plurality of pin members tobe rotated and effect translation of adjacent ones of said pin memberswithout effecting rotation thereof.

1. A mechanical memory system for effecting a predetermined permutationof switch positions of a plurality of switching means comprising, aplurality of code pin members; each pin member having a substantiallysquare face member, a slot formed in said face member and extendingtransversely between parallel sides thereof; means for containing saidplurality of pin members in a row with coplanar face members, saidcontaining means permitting rotation of each of said pin face memberswithin the plane defined by said pin face members, said containing meanspermitting translation of said pin members along the axis defined bysaid row of pins, spring loading means cooperating with at least one ofthe pins in said row and urging said plurality of pins into acompression loaded parallel-sided orientation; said plurality ofswitching means arranged in a row with each of said switching meansincluding an actuating arm member in spring loaded relationship with theface member of an associated one of said plurality of pin members, eachof said actuating arm members being urged into a first position when acooperating one of said pin member slots is coextensive with the axis ofsaid switch actuating arm and being urged into a second position when acooperating one of said pin member slots is transverse the cooperatingactuating arm axis, and means responsive to said first and second switchactuating arm positions to effect respective predetermined first andsecond electrical interconnections.
 2. A mechanical memory system asdefined in claim 1 wherein said pin row containing means comprises firstand second fixed mounting surfaces between which said pin row isconfined, said mounting surfaces being space separated by apredetermined distance in excess of the pin row length, said springloading means comprising a compression spring member carried with theconfines of said pin row and acting along the pin row axis to urge saidplurality of pin members into said spring-loaded parallel-sidedorientation.
 3. A mechanical memory system as defined in claim 1 whereinsaid pin row containing means comprises a pair of parallel spaced guiderail members fixed between first and second mounting plate members, eachof said pin members having formed therein a radial groove the diameterof which substantially equals the distance by which said guide railmembers are separated, said rail members being received into said pinmember radial grooves, whereby said pin members are constrained fromtranslation transverse that of said guide rail axes with limitedtranslation permissible along the pin row axis parallel to that of saidguide rail members and with each of said pin members being rotatablewithin the plane defined by said pin face members.
 4. A mechanicalmemory system as defined in claim 3 wherein each of said square pinmember faces is formed with rounded corners of predetermined radius,said pin members being constructed of a lubricous material permitting aselected one of said plurality of pin members to be rotated and effecttranslation of adjacent ones of said pin members without effectingrotation thereof.
 5. A mechanical memory system comprising a pluralityof code pin members arranged in a row, each said code pin member beingformed with a substantially square face, means for containing said pinmembers in said row to permit rotation of each pin member within theplane defined by said pin member faces and to permit translation of saidpin members along the axis of said pin row while constraining said pinmembers from translation transverse that of said pin row axis, springloading means cooperating with at least one of the pin members in saidrow and urging said plurality of pin members into a compression loadedparallel-sided orientation, each of said pin member faces having atransverse slot extending between parallel sides thereof; a plurality ofswitching means arranged in a row, each said switching means includingan actuating arm member adapted to be urged into spring-loadedengagement with the face of an individual associated one of said pinmembers in said row, said actuating arm members having at least a pinface addressing portion thereof with transverse dimension less than thatof the width of said pin face slots, whereby those of said actuating armmembers addressing a pin face the slot of which is coextensive with theactuating arm member axis are positioned to a first position and thoseof said actuating members addressing a pin face the slot of which istransverse the actuating arm axis are positioned to a second position,and electrical contact means associated with the actuating arm member ofeach of said switching means to effect predetermined first and secondelectrical connections in response to respective first and secondpositions of the associated actuating arm.
 6. A mechanical memory systemas defined in claim 5 wherein said pin members are formed of aninsulating material, said switching means actuator arm memberscomprising a conductive material, one end of each said actuating armmember comprising a first output terminal, and further contact meansadapted to make a first predetermined electrical connection with theother end of said actuating arm with said actuating arm in the firstposition thereof, and a second predetermined electrical connection withthe other end of said actuating arm with said actuating arm in thesecond position thereof.
 7. A mechanical memory system as defined Inclaim 5 wherein each of said square pin member faces is formed withrounded corners of predetermined radius, said pin members beingconstructed of a lubricous material permitting a selected one of saidplurality of pin members to be rotated and effect translation ofadjacent ones of said pin members without effecting rotation thereof. 8.A mechanical memory system comprising a plurality of parallel rows ofcode pin members; each of said plurality of rows of code pin memberscomprising a plurality of code pin members arranged in said row, eachsaid code pin member being formed with a substantially square face,means for containing said pin members in said row to permit rotation ofeach pin member within the plane defined by said pin member faces and topermit translation of said pin members along the axis of said pin rowwhile constraining said pin members from translation transverse that ofsaid pin row axis, spring loading means cooperating with at least one ofthe pin members in said row and urging said plurality of pin membersinto a compression loaded parallel-sided orientation, each of said pinmember faces having a transverse slot extending between parallel sidesthereof; a plurality of switching means arranged in a row parallel thatof said rows of code pin members; each said switching means including anactuating arm member adapted to be urged into spring loaded engagementwith the face of an individual associated one of said pins in a selectedone of said rows of code pin members, said actuating arm member having atransverse pin addressing dimension less than that of the width of saidpin face slots whereby those of said actuating arm members addressing apin face the slot of which is coextensive with the actuating arm memberaxis are positioned to a first position and those of said actuating armmembers addressing a pin face the slot of which is transverse theactuating arm axis are positioned to a second position, electricalcontact means associated with the actuating arm members of each of saidswitching means to effect predetermined first and second electricalconnections in response to respective first and second positions of theassociated one of said actuating arm members, and means for selectivelypositioning a selected one of said rows of code pin members intocooperative engagement with said plurality of switching means.
 9. Amechanical memory system as defined in claim 8 wherein the pin membercontaining means for each of said rows of pin members comprises a pairof parallel-spaced guide rail members fixed between first and secondmounting plate members, each of the pin members in a row of said pinmembers having formed therein a radial groove the diameter of whichsubstantially equals the space separation of said guide rail memberpair, said rail members being received into said pin member radialgrooves, whereby said pin members are constrained from translationtransverse that of the axes of said guide rail members with limitedtranslation permissible along the pin row axis parallel to that of saidguide rail members and with each of said pins in said row beingrotatable within the plane defined by said pin face members in said pinrow.
 10. A mechanical memory system as defined in claim 9 wherein saidpairs of parallel-spaced guide rail members comprise adjacent ones of aplurality of guide rail members arranged about the periphery of a drum,and said means for selectively effecting cooperative engagement betweena selected one of said rows of pin members and said row of switchingmeans comprises means for rotating said drum to a preselected angularposition.
 11. A mechanical memory system as defined in claim 8 whereineach of said square pin member faces is formed with rounded corners ofpredetermined radius, said pin members being constructed of a lubricousmaterial permitting a selected one of said plurality of pin members tobe rotated and effect translation of adjacent ones of said pin memberswithout effecting rotation thereof.